Robert Anthony Schaut

A New Glass Option for Parenteral Packaging

TECHNICAL ABSTRACT: Glass is the ideal material for parenteral packaging because of its chemical durability, hermeticity, strength, cleanliness, and transparency. Alkali borosilicate glasses have been used successfully for a long time, but they do have some issues relating to breakage, delamination, and variation in hydrolytic performance. In this paper, alkali aluminosilicate glasses are introduced as a possible alternative to alkali borosilicate glasses. An example alkali aluminosilicate glass is shown to meet the compendial requirements, and to have similar thermal, optical, and mechanical attributes as the current alkali borosilicate glasses. In addition, the alkali aluminosilicate performed as well or better than the current alkali borosilicates in extractables tests and stability studies, which suggests that it would be suitable for use with the studied liquid product formulation. LAY ABSTRACT: The physical, mechanical, and optical properties of glass make it an ideal material for packaging injectable drugs and biologics. Alkali borosilicate glasses have been used successfully for a long time for these applications, but there are some issues. In this paper, alkali aluminosilicate glasses are introduced as a possible alternative to alkali borosilicate glasses. An example alkali aluminosilicate glass is shown to meet the requirements for packaging injectable drugs and biologics, and to be suitable for use with a particular liquid drug.

Historical review of glasses used for parenteral packaging

Glass has long been used for packaging precious liquids, in particular pharmaceuticals. Its unique combination of hermeticity, transparency, strength, and chemical durability make it the optimal material for such an important role. Todays life-saving drugs are stored in borosilicate glasses, which evolved from applications in microscope optics and thermometers. As the glass compositions improved, so did the methods used to shape them and the tests used to characterize them. While all of these advances improved the quality of the glass container and its ability to protect the contents, problems still exist such as delamination, cracks, and glass particulates. In addition to these issues, we review new developments in glass composition development, performance, and testing in the 21st century.

Enhancing patient safety through the use of a pharmaceutical glass designed to prevent cracked containers

An essential role of packaging material for the storage and delivery of drug products is to provide adequate protection against contamination and loss of sterility. This is especially important for parenteral containers, as lack of sterility or contamination can result in serious adverse events including death. Nonetheless, cracked parenteral containers are an important source of container integrity failures for injectable drugs and pose a serious risk for patients. Despite significant investments in inspection technology, each year many injectable drugs are investigated and recalled for sterility risks associated with cracked borosilicate containers. Multiple studies and the many difficulties in detection of cracked containers suggest that the magnitude of the public health risk is even larger than the recall rate would suggest. Here we show that the root cause of cracked parenteral containers (low internal energy following annealing) is inherent to the glasses currently used for primary packaging of the majority of injectable drugs. We also describe a strengthened aluminosilicate glass that has been designed to prevent cracks in parenteral containers through the use of an engineered stress profile in the glass. Laboratory tests that simulate common filling line damage events show that the strengthened aluminosilicate glass is highly effective at preventing cracks. Significant safety benefits have been demonstrated in other industries from the use of special stress profiles in glass components to mitigate failure modes that may result in harm to humans. Those examples combined with the results described here suggest that a significant improvement in patient safety can be achieved through the use of strengthened aluminosilicate glass for parenteral containers. LAY ABSTRACT: Cracks are small cuts or gaps in a container which provide a pathway for liquid, gas, or microbes through a glass container. When these defects are introduced to conventional glass containers holding injectable medicines, the affected drug can pose serious risks to the patient receiving that medication. Specifically, the drug product may become less effective or even non-sterile, which could lead to bloodstream infections and, in some cases, death. This article presents a review of some previously documented cases of cracked glass containers that led to patient infections and deaths. Following a survey of common crack locations in glass vials, lab-based methods for replicating these cracks are presented. These methods are then used to compare the fracture response of vials made from conventional borosilicate glass and strengthened aluminosilicate glass. The results show that stable cracks are essentially prevented (at least 31 times less likely to occur) in the strengthened aluminosilicate glass containers (relative to conventional borosilicate glass). This improvement in safety is similar to improvements already engineered into other glass product designs by utilizing stored strain energy to mitigate certain failure modes.